Fluid-pressure turbine



Cm E. MELLIN. FLUID PRESSURE TURBINE. APPLICATION FILED JUNE 6.. 1919.

1,431,74 l Patented Oct. 10,1922.

3 SHEETS-SHEET l.

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WITNESEES c.. E. MELL I'N'.

FLUID PRESSURE TURBINE. APPLICATION FILED JUNE 6. I9I9- 1,431,748. Patented Oct. 10,1922

3 SHEETS-SHEET Z.

c. E. MELLIN. FLUID PRESSURE TURBINE. APPLICATIOIN FILED JUNE 611919.

Bamntd Oct. 10,1922.

3 SHEETS-SHEET 3.

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Patented @et. lW, i922.

r lhtlqfllfillo CARL EUGENE MELLIN, OF SCHENECTADY, NEW YORK.

FLUID-PRESSURE TURBINE.

Application filed June 6, 1919. Serial No. 302,175.

a plurality of discs or plates secured on a rotatable shaft.-

The object of my invention is to provide a turbine of such type which shall be of simple, strong, and inexpensive construction, and low maintenance cost, and in the operation of which the energy of the actuating fluid shall be efficiently exerted with the lowest practicable resistance from friction and axial forces.

. The improvement claimed is hereinafter fully set forth. I 4

In the accompanying drawings: Figure 1 is a view, half in end elevation, and half in vertical transverse section, on.the line a a of Fig. 2, of a fluid pressure turbine, illustrating an embodiment of'my invention; Fig. 2, a vertical longitudinal section through the same, on the line 7) b of Fig. 1; Figs. partial transverse sections, on an enlarged scale, illustrating, respectively, different forms of buckets; and, Figs. 5, 6, 7 and 8, partial longitudinal sections, illustratin variations of structural detail in the blac es and carrying discs.

In the practice ofmy invention,referring descriptively to the specific embodiment thereof which is herein exemplified, a main or driving shaft, 1, is journaled in bearings, 2 fixed upon a frame, or bed plate, 2, which, in this instance, is shown as formed integral wit-h the heads, of the turbine casing, 3. The shaft. 1. passes through stuffing boxes, 3", in the heads of the casing, and has secured upon it, within the casing, a'wheel or rotor, which isln the form of one or more plates or--discs, 4, a plurality thereof beingherein illustrated. Motive fluid is admitted to the casing, at its periphery, from a supply passage, 5,

through nozzles, p6, inclined at an acute angle to the periphery of the casing, and controlled by valves, 7, in the ordinary man ner. The motive fluid impinges at an acute angle on blades or buckets fixed on the plates, 4, thereby imparting rotary motion walls of either curved, as shown,

heads, 9

to said plates and the driving shaft, 1, after which impingement it is discharged from the opposite side of the casing, through an exhaust passage, 8, to the atmosphere or to a condenser.

A plurality of blades or buckets, 9, is rigidly secured to each of the plates or discs, 4, said blades being inwardly curved or inclined, at an acute angle, to tangents of these circular plates, and forming the passages through which the motive fluid which is supplied to the casing, from .the nozzles, 65, at a more or less acute angle to the periphery of the casing, passes to the interior of the casing, and thence to the exhaust passage, 8. The blades, 9, may be or straight, and are terminated, at their inner ends, by extending laterally from their bodies, the faces of which heads are curved or inclined transversely to the middle lines of the plates, thereby causing the passages between them to be turned inwardly at their inner or discharge ends, by which an approximate reversal of the currents of motive fluid is effected as it leaves them. The blades may be either toothed or notchec on one or both sides, or have unbroken or plain surfaces. The toothed or notched form of blades, which is illustrated in Figs. 1 and 3, is deemed preferable by me, for the reason that the teeth or notches cause the currents of motive fluid to expend their inertia more effectively, and in a shorter distance, than if the walls of the passages were smoother plain, as in the form shown The'velocity of the currents entering the passages between the blades is three to four times as great as that'of the peripheries of the plates, and the currents impinge against the teeth at oblique angles, and are deflected in and out, in a zig-zag course. The higher velocity of the current induces a reduction of pressure on what may be termed the lee sides of the teeth, i. e., those opposite the driving sides on which the currents act, as the fluid expands radially from the middle lines of the currents, which are carried forward, similarly to the gases leaving the muzzle of a guinand the action of the currents against the lee. sides of the teeth becomes considerably less than on the driving sides. In other words, a reduction of pressure or partial vacuum is caused on the lee sides of the teeth, the difference of pressure between which and the impact pressure on the driving sides constitutes the impelling force on each tooth. The .center or core of the current does not follow the contour of the toothed or notched passage, but makes a partial deflection between the two sides, imparting speed to the sides of the current that are in contact with the walls of the passage.

The friction of the current of motive fluid on the sides of the passage is also a substantial inipelling force, as the resultant from both sides falls the same as the teeth, close to a tangent of the plate with a proper curvature or inclination of the passage. While some heat is generated by the friction, this serves to delay condensation to the discharge portion of the passage and contributes in maintaining a higher velocity of the current in the latter part of its path.

By reason of centrifugal force, water of condensation will not follow dry steam to its exhaust, but is separated therefrom inthe passage between the blades and discharged through passages, 9 to the periphery of the plate, after having given up all its inertia above that due to the velocity of the plate. The direction of this passage being opposite to the flow of the steam, the steam cannot enter it.

The blades, 9, and consequently the passages between them, are preferably gradually widened, as shown, from the periphery 'of the plates on which they are carried,

towards the shaft, to afford freedom for expansion of the motivefluid, and an increased area for the action of the decreasing velocity of the currents, as they approachthe inner ends of these paths. To effect this widening of the blades, the portions of the plates, 4:, to which the blades are attached, may be outwardly or laterallytapered or inclined, this inclination being formed on the inner sides only of the end plates, when a plurality of plates is applied, and on both sides of the intermediate plates, which then become of V section adjacent. to their peripheries, as clearly shown in Fig. 2. The V section plates are shown, on' a larger scale, in Figs. 5 and 8.

The blades, 9, may be made integral with the plates or be welded thereto, or be separate pieces secured to the plates by bolts, 9, or rivets. The plates should be recessed by annular grooves, to form abutment shoulders for the'blades, for the purpose of opposing the centrifugal force which tends to sep arate the blades from the plates when rotat ing at high speed. l/Vhen the turbine comprises a plurality of plates, as in the instance exemplified, the blades of adjacent plates may abut midway between the plates, as shown in Fig. 1, each of the plates, except the end ones, having blades on each side, as shown on a larger scale in Fig. 5. Figs. 6,

7, and 8 illustrate the relation-oftheplate and blades, when only one plate is applied in the turbine, that of Fig. 6 having blades on one side only, and those of Figs. 7 and 8 having blades on both sides. In each of these constructions, the sides of the passages between the plates which are further from the plates, are closed by rings, 9, of plate metal, between which and the plates, the blades are held rigidly by the bolts, 9. When the blades are made separate from the plates, they may be formed by drop forging, without finishing on their toothed sides, except at. their ends.

The plates, at, should be made of the strongest material, in order to be as light as possible, and when spoked, the spokes should be shaped to act in the manner of fans, to facilitate the flow of the exhaust motive fluid from the inside of the casing to the atmosphere or the condenser, that is to say, their transverse sides should be inclined to lead in the direction of the rotation of the shaft, as indicated in Figs. 1, 3 and 4:.

The casing, 3, of theturbine, is herein shown as diametrically divided horizontally, but may be divided on an angle,'in which case fluid supply nozzles maybe disposed directly or diametrically opposite each other,

the blades may be made practically continuone for two thirds or three quarters of the periphery of the casing. Forward and reverse plates and blades may, if desired, be located in a single casing, suitable change valves being applied to turn the fluid pressure from the rotatory members of one direction to those of the other, or'the forward and reverse members may be located in separate casings, as circumstances may render more desirable. I I It will be seen that the turbine above described is structurally simple, can be manufactured almost entirely by machine work, and is of ample strength, containing no members which are reasonably liable to breakage in service Its cost of construction and maintenance will be the least of any motor of the type of equal power, and the weight and space occupied shouldlnot exceed those of any other motor of equal power. Substantially all the energy of the motive fluid, in leaving the supply nozzle or nozzles, is converted into power, less that that may be retained in exhaust steam after it has left the blades, as all friction exerted works pracforces, and no loss in frictionof thrust bean ings, none being required,

I claim as my invention and desire to secure by Letters Patent:

1. A fluid pressure turbine wheel having a plurality of blades with a plurality of notches on their working faces and each blade terminating in an enlarged head at its inner end, comprising forwardly and rearwardly extending curved portions.

2. A fluid pressure turbine wheel having a plurality of blades extending inwardly from the periphery of the wheel, and each blade terminating in an enlarged head at its inner end, comprising a forwardly and rearwardly extending curved portion.

3. A fluid pressure turbine wheel having a. plurality of discs and a plurality of interposed blades, said blades provided with ridges and extending inwardly from the periphery of the wheel, each blade ter1ninating in an enlarged head at its inner end, comprising aforwardly and rea-rwardly extending curved portion, a casing inclosing said discs and blades, fluid supply nozzles opening into the casing in position to dis charge into the space between the blades, and an exhaust passage leading out of said casing.

5 In a fluid pressure turbine, the combination of a shaft; a plurality of spoked plates secured thereon, the sides of the spokes of said plates being transversely inclined to facilitate the flow of motive fluid; a plurality of blades interposed between and fixed to said plates and extending inwardly From the periphery thereof, at acute angles to radii; a casing enclosing said plates and blades; fluid supply nozzles opening into the casing, in position to discharge into the spaces between the blades; and an exhaust passage leading out of the casing.

CARL EUGENE MELLIN. lVitnesses CLARENCE. W. TRENDELL, CARL W. CUTLER. 

